In this research, I examined the process of establishing the licensed prostitution system in Colonial Taiwan and Korea under control in Japanese Empire. In spite of various differences in the process to establishment and the content, we can point out some common basic characters of both : the medical examination system of venereal disease, the policy of collecting brothels, and so on.The introduction of the licensed prostitution system into Colonial Taiwan started in 1896 immediately after owning of Japan. The system was united in all of Taiwan in 1906 though had been different in each region. On the other hand, it was also united in Colonial Korea in 1916, and the phenomenon that the Korean prostitutes went abroad happened at the time of World War I.Korean prostitutes started making a passage to Taiwan at the beginning of 1920's, came to excee dTaiwanese prostitutes in 1930, and to occupy about 1/4 of the numbers of licensed prostitutes of Taiwan in about 1940. Because of the lowest age of the licensed prostitute permission in Japanese Colonial Empire (16 years old), not onlythe Japanese but also Korean prostitutes made apassage for Taiwan. And, the existence of the Korean prostitutes in Taiwan invited the situation in which a lot of Korean "Comfort women" was sent to the battlefield in the Canton provinces via Taiwan at the period of China Japanese War.